1. Technical Field
The present invention relates to an improved bracket or hanger for dual use for supporting fluid-carrying ducts between adjacent joists in a building structure as well as water lines.
2. Background Information
As is well known in heating, cooling, ventilating and air-conditioning systems (HVAC systems) in residential homes, condominiums, apartments, office buildings and other building structures, the duct members are usually comprised of metallic pipes, hollow composite materials such as tubes, and the like supported from and between floor or ceiling joists. It is common practice for the HVAC system to include an elongated primary or main duct from which extends a series of smaller branch or fluid-distributing ducts which are mounted between adjoining floor or ceiling joists and are parallel thereto. Such main and branch duct members which are located between joists are normally supported by metal wires or adjustable metal hangers which are placed between the joists in transverse supporting relation and are attached thereto by various means.
In addition, the ducts may be supported by such hangers or brackets and water supply and waste water lines may also be so supported. This invention pertains to a more universal improved bracket for dual use for supporting air ducts and water lines.
Normally the adjustable metal hangers have a substantial depth of section which is not readily amenable to expeditious cutting to length to fit between non-uniform adjoining joists. Also non-uniformity of the spacing between adjacent joists creates an installation problem. The sometimes variable distances between adjacent joists prevent the utilization of duct hangers having standard uniform lengths. In addition, the pointed ends or tapered prongs on the ends of certain types of adjustable hangers are not easily or satisfactorily driven into wooden joists at desired locations or at prescribed spacing due to imperfections in the wooden joists such as knots, holes, cracks and the like. The prongs sometimes break off during installation rendering the bracket useless for the intended purpose. The pointed ends or prongs are occasionally only partially or incompletely seated in the joists and lose their load-carrying ability at one end or the other in time, allowing the duct or pipe to sag, loosen or break. Also the metallic hangers create a heat transfer loss from the ducts to the hangers, and in addition cause a noise and vibration problem due to air flow in the ducts and resonance noise in the floors, ceilings and surrounding areas. The vibration and resonance contributes to the unseating of the hanger ends. The prior art hangers are only horizontally adjustable and cannot be vertically adjustable for their mounting between the joists.
U.S. Pat. No. 3,163,386 discloses an adjustable duct hanger having tapered prongs at its ends which are not easily or satisfactorily driven into the joists for the aforesaid reasons. Also the two telescopic sections are more expensive to manufacture and assemble. U.S. Pat. No. 5,024,403 discloses a pipe hanger having an upper rectangular plate of prescribed length which is difficult to sever, and ends which cannot penetrate the joists easily or satisfactorily. There are other adjustable hangers in the prior art such as disclosed in U.S. Pat. No. 3,285,553 which experience mounting problems due to their wedge-shaped prongs. And, as stated, all impart vibration and noise to the floor and ceiling joists due to operational mechanical components such as motors and fans associated with the HVAC ducts because of their all-metal construction and interconnection. As stated, known hangers can only be adjusted horizontally to fit between adjacent joists. None can be adjusted vertically in full supporting relation beneath the ducts or water lines.